My Google Pr Dropped

About a year ago my site dropped from a PR4 to a PR3. At the time a lot of people said the same thing happened to them, just Google doing their thing.

Now my PR went from PR3 to PR2 in the last day or two. Is this one just me or did this happen to a lot of you out there this week as well.

I've been revising pages on my site over the last 2-3 months and traffic has never been higher. Other than that, I don't know. Don't worry about PR right?? Going below PR3 is a psychological barrier I didn't want to see.

I just haven't had time to devote to links and maybe over time I'm slowly losing the ones I had. Could that have a bearing on things.